Ceiling-mold.



UNITED ,sTATEs PATENT OFFICE.

JACOB BQ Emiv'or PITTSBUEG,*"PENNSYLVANIA, AssIGNoE To BLAW coLmPsiELE STEEL CENTEEINC COMPANY, OE PITTSEURG, PENN- sYLvANIaA CORPORATION OF NEW JERSEY.

CEILING-MOLD.

Speccation of Letters Patent.

Patented may 2'1, 1907.

Application led November l2, 1906. Serial Nn. .343,008.

T all whom it may concern:

Be it known that I, JACOB B. BLAw,'a citizen of the United States, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Ceiling-Molds, of which the following is a specifica-tion.

My invention relates to molds for concrete ceilings; and has for its objects; to produce a mold which can be readily released from the concrete; to produce a mold which shall be When in position for molding, very stiff and unyielding; and'nally to provide a mold of minimum weight and great simplicity which shall be of more durable constructionand less expensive than the wooden molds now in use. One embodiment of my invention is illustrated in the accompanying drawing in which,

Figure l is an end view of a mold member, and

Figure 2 is a plan view of the under side of the mold member of Figure 1.

My mold is preferably constructed of thin sheet metal which can be easily handled andfurthermore can be detached from concrete after it has setby a gradual or peeling action, and without hammering or jarring which has a tendency to crack the concrete. Heretofore wooden molds have been used for .the concrete,y but such molds fail t-o produce a smooth surface, are detached with ditliculty, are cumbersbme and expensive, and can be used only a few times. My mold on the other hand., produces a smooth surface, can be de- ,ta'clied easily, is cheap and practically indestructible.

Referring to the drawing, the mold illustrated is composed of three members, two of which are the corner members 1 and 2, and the third is the central member 3 connecting such corner members 1 and 2. The corner members are shown of thin sheet metal shaped to the desired curve and provided with means for loosening from the concrete after it has set, which means consist in the turubuclrles 4, which turnbuckles l engage the edges of the members 1 and 2 respectively by means of the angle irons 5 and 6 to which the turnbuclles are detachably secured by means of the bolts shown. The members l and 2 are secured to either end of the member 3 by .neans of the straps 7 which straps are riveted of the sheet. This construction of the plate vcorner sect-ions provided with collapsing to the members 1 and 2 and are provided-at their other ends with slots. for receiving the 5 5 loops S, which loopsare secured to the member 3. The loops are held in position by means of wedges 9 passing therethrough as indicated in Figure 2. The central member 3 is preferits flat shape is reinforced by longitudinal' vstitfeningsections 10 Which-in the presentcase are angle ironsriveted to the under side the weight of metal used. y

In operation, the V:mold sections 1, 2, 3, are secured together and placed in the position shown in Figure 1 being supported from beneath by means of the side walls or any form of temporary side posts or pillars available and the concrete is spread over the top of the mold member to the Adesired thickness and allowed to` set. After the material' has set 3 gives a maximum amount of rigidity for the corner pieces. are irst loosened by contracting the turn'buckles 4 thereby loosening the edges of the corner pieces and gradually peeling the metal away from the concrete. After t-he members l and 2 have been loosened and 'removed the member 3 can be easily loosened from the, ceiling, and the whole apparatus remoy-edjto a new position. The member can be made of any desired,

length convenient for handling and if found ber 3 could be made in a number ofrdetach-f able sections. d :f

Having thus described my invention and illustrated its use, what I clain1"-as`ne\v.;and desire to secure by Letters Patent, is the fol-L lowing: l a l v 1. In combination, al mold-composedof'. exible material comprising a pair of curved means extending between. the ends ofeach section, and acentral section adapted to be removably secured to the cornensections and provided with stifi'ening sections.

2. In combination, a mold composed of tiexible material comprising a pair of curved corner sections provided with turnbuckles ext-ending bet een the ends of each section, and a central section adapted to be removably secured to the corner sections and p rom5 vided with stiifening sections.

necessary in the case of a wide arch'theginem- IOC 3;- h1 combination, a .mod' composed of testimony whereof,- I hereunto sign my fexible matelal and comprising curved corn'ame in the presence of the two subscribed ner'portionssnd a substantially Hat central Witnesses.

portion iiltelfposod between the corner por#A JACOB B. BLAW.. -5 'tions aVndQ-'povded' lwithlstffnlng.setions, ,Witnesst v -andstifenng andcollapsing braces extend- J. C. BRADLEY, -f ing across the curves ofthe corner portions.4 ARCHWORTH MARTIN. 

